JPH0985843A - Frp lattice and its preparation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an FRP lattice which exhibits excellent chem. resistance and high rigidity and makes prediction of breakage possible to result in safety and makes wt. reduction possible furthermore. SOLUTION: An FRP lattice with a wt. of at most 15kg/m<2> , and a bending rigidity of at least 0.7×10<6> kgf.mm<2> or a bending strength of at least 40kgf/mm<2> and prepd. by arranging reinforcing fibers in laminar shape and making them with a resin to a composite, is provided and the reinforcing fibers contain a high tensile elasticity reinforcing fiber and a low tensile elasticity reinforcing fiber and at least outer layers 2a and 2b contain the high tensile elasticity reinforcing fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber reinforced plastic (FRP) lattice and a method for producing the same, and more particularly, to an FR suitably used in the fields of civil engineering and construction.
The present invention relates to a P lattice and a method for manufacturing the same.

[0002]

2. Description of the Related Art Glass fiber reinforced plastic (GFR)
Grid members made of P) are used for flooring materials where contact resistance and drainage are required, such as plating plants and sewage treatment plants, as well as passages for high-place construction where light weight and strength are required, and balconies. 2. Description of the Related Art Floor materials, lids such as road gutters and yards, and wall materials and ceiling materials are used for various purposes as members in the civil engineering and construction fields.

[0003] Compared to iron used in these fields, GFRP has a feature that it has excellent touch resistance and does not rust. However, since its elastic modulus is smaller than that of iron, a lattice member made of GFRP has a bending rigidity. Small or low shear rigidity,
When used as a member in the civil engineering and construction fields, various problems occur.

[0004] For example, when used as a lid for a gutter on a road, when a heavy vehicle rides on the top, the amount of deflection of the lid increases, the GFRP lattice lid is greatly deformed, and the edge of the GFRP lid is lifted, and the surrounding GFRP lid is lifted. Large gaps or steps are created between them, and people walking may be pinched or tripped.

When used for wall materials and ceiling materials, they suppress deformation of the building in the event of an earthquake and contribute to the improvement of the seismic resistance of the building. turn into. It is possible to increase rigidity by increasing the height of the GFRP member or the width of the lattice bar, but the space for incorporating the member becomes larger, the aperture ratio becomes smaller, and drainage becomes worse. Or In addition, there is also a problem that the visibility is deteriorated, which gives a sense of pressure to human beings, the ventilation is deteriorated, and the weight becomes heavy.

A GFRP made of glass fiber and resin
Although is lighter and stronger than iron, it does not plastically deform like iron and causes brittle fracture at a stretch. When reinforcing fibers and resins are deteriorated by chemicals or ultraviolet rays when used for various flooring materials and the like, the strength deteriorates. Therefore, an undesired destruction condition may suddenly occur.

Further, although the GFRP lattice member is lighter than the iron lattice member, since the civil engineering / construction work place is generally a work place involving heavy labor, there is a strong demand for further weight reduction of various members to be handled.

As a method of manufacturing such a GFRP lattice member, a reinforcing fiber bundle is preliminarily impregnated with a resin (hereinafter, referred to as a wet state) and aligned to form a forming die in which forming grooves are arranged in a lattice form. A method of curing and demolding after stacking has been adopted. However, this method has a problem that the laminating operation time is limited by the pot life of the resin, a large lattice member cannot be manufactured, and the reinforcing fiber in a wet state has a slippery surface, and sufficient tension is not applied during the laminating operation. Meandering in the molding groove of the mold, the strength of the lattice member,
There was a problem that rigidity was reduced.

As a solution to such a problem, a state in which the reinforcing fiber bundle is not impregnated with resin (hereinafter referred to as a dry state).
A method is conceivable in which the layer is laminated on a molding die by, and then a resin is injected into this molding die to impregnate the reinforcing fiber bundle and cure. However, even with this method, it takes time to impregnate the reinforcing fiber bundle on the bottom side of the molding groove, the production efficiency drops, and the air remaining in the fiber bundle does not completely escape and remains as a void after resin curing. However, there is a problem that the strength and rigidity of the lattice member are reduced.

[0010]

The problem of the present invention is to pay attention to such a situation, to provide excellent chemical resistance, high strength and rigidity, predictable fracture and safety, and further It is to provide an FRP grating that can be made lightweight.

Another object of the present invention is that the resin can be manufactured in any size without being affected by the pot life of the resin, and the like.
Another object of the present invention is to provide a mold and a method for producing a FRP lattice having high strength and rigidity in a voidless manner.

[0012]

In order to solve the above problems, the FRP grating according to the present invention has a weight of 15 kg / m ^2.
And flexural rigidity of at least 0.7 × 10
It is characterized by being ⁶ kgf · mm ² .

The FRP lattice according to the present invention is characterized by having a weight of 15 kg / m ² or less and a bending strength of at least 40 kgf / mm ² .

Such an FRP grating is achieved by the following structure. That is, the FRP lattice according to the present invention has a structure in which reinforcing fibers are arranged in layers and are combined with resin.
An RP lattice, wherein the reinforcing fibers include high tensile elastic modulus reinforcing fibers and low tensile elastic modulus reinforcing fibers, and at least the outer layer includes high tensile elastic modulus reinforcing fibers. .

In such an FRP grating, the aperture ratio is preferably in the range of 65 to 95%. Further, it is preferable that the cross-sectional shape of the frame forming the grid eyes is an inverted trapezoidal shape. Furthermore, the shape which has a step part in the cross section of the frame which forms the eyes of a lattice can also be used. However, the cross-sectional shape of the lattice is not limited to these shapes, but can be any shape.

The resin constituting the FRP lattice is not particularly limited, but vinyl ester resin is preferable. Preferably, the high tensile modulus reinforcing fiber is a carbon fiber, and the tensile modulus of the high tensile modulus reinforcing fiber is at least three times that of the low tensile modulus reinforcing fiber. Furthermore, it is preferable that the thickness of the outer layer accounts for at least 20% of the total thickness.

Further, the weight of the FRP lattice constructed as described above is preferably 15 kg / m ² or less, which makes it possible to meet the demand for weight reduction while ensuring rigidity and strength. The flexural rigidity of the FRP lattice depends on the application but is preferably at least 0.7 × 10 ⁶ kgf · mm ² , and the flexural strength is at least 40 kg.
It is preferably f / mm ² .

Further, the mold for the FRP lattice according to the present invention is an FR in which reinforcing fibers are arranged in layers and are compounded with a resin.
A mold for a P-lattice, which is characterized in that a groove extending in the thickness direction of the mold is provided on the side wall of the mold for forming the meshes of the lattice. The FRP lattice molded by using such a mold has a ridge extending in the thickness direction of the lattice on the side surface of the frame forming the mesh of the lattice.

Further, in the method for producing an FRP lattice according to the present invention, when reinforcing fibers are arranged in layers in a molding die and resin is injected to produce an FRP lattice, the reinforcing fibers are reinforced with high tensile modulus. The method comprises using fibers and low tensile elastic modulus reinforcing fibers, and disposing high tensile elastic modulus reinforcing fibers in at least an outer layer.

Further, the method for manufacturing an FRP lattice according to the present invention uses a forming die in which a groove extending in the thickness direction of the forming die is provided on the side wall of the die for forming the mesh of the lattice as described above. Reinforcing fibers are arranged in layers in the mold and resin is injected to make F
The method comprises manufacturing an RP grating. Also in this case, it is preferable to use the high tensile elastic modulus reinforcing fiber and the low tensile elastic modulus reinforcing fiber, and arrange the high tensile elastic modulus reinforcing fiber in at least the outer layer.

In the above FRP lattice manufacturing method, it is preferable to use a vinyl ester resin as the resin.
Preferably, carbon fibers are used as the high tensile modulus reinforcing fibers, and glass fibers are used as the low tensile modulus reinforcing fibers.

In addition, in these FRP lattice manufacturing methods, it is preferable to carry out molding under reduced pressure.

Various civil engineering and construction members can be constructed by using the FRP lattice according to the present invention as described above. The FRP lattice according to the present invention includes, for example, various flooring materials, passage materials (for example, scaffolding materials) for high-place construction, lids (groove lids, ridge lids) such as road gutters and pits, various wall materials and the like. It can be used as a ceiling material (for example, a wall material on which a decorative board or the like is arranged on its surface or a core material of a ceiling material). More specifically, for example, in the case of water, floorboards and corridors of sewage (sewage) treatment plants, leisure facilities, floorboards of ships, marine structures, etc. In the case of chemicals, petroleum refining and chemical plant construction For construction and bridges, such as flooring materials, stairs, and wall materials in places that require radio wave transmission, such as flooring materials and radar surroundings, walkways of high-rise buildings, treads of emergency stairs, floors of balconies, fences (for example, verandas) Fences, general fences and partitions),
Core materials for doors, floor materials for parking lots, walkways for suspension bridges and piers, inspection walkways for railway bridges, etc., floor materials and walls for clean rooms, ceiling materials,
There are a heliport floor plate and the like, and in addition, there are a plating tank, a floor plate around a tower, a lid of a drainage / drainage groove (for example, a lid of a manhole, a groove lid) and the like.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 and FIG.
1 illustrates an FRP grating according to one embodiment of the present invention. In FIG. 1, 1 indicates the entire FRP lattice, and the FR
The P-lattice 1 is composed of reinforcing fibers arranged in two directions and in a layered form and compounded with a resin. That is, a large number of aligned reinforcing fibers are alternately laminated in two directions to form a lattice shape, and these are combined with a resin. Further, the fiber volume content is set to be about 30%. The FRP grating 1 according to the present embodiment is used, for example, as a member for a part where touch resistance, drainage, durability, and the like are required.

The cross-sectional shape of each grid bar of the FRP grid 1, that is, the cross-sectional shape of the frame forming the grid eyes is formed in an inverted trapezoidal shape as shown in FIG. And
Each lattice bar is a three-layer structure of substantially two kinds of layers, in which layers 2a and 2b containing high tensile elastic modulus reinforcing fibers are arranged in both outermost layers, and layer 3 containing low tensile elastic modulus reinforcing fibers is arranged in the central layer. Is configured.

The reinforcing fibers used in the outermost layers 2a and 2b are preferably high strength / high elastic modulus fibers such as carbon fibers, silicon carbide fibers and metal fibers composed of multifilaments. Among them, carbon fiber has excellent chemical resistance, water resistance, etc., is lightweight, has high strength, high elastic modulus, and also has good resin impregnating property and adhesiveness with resin, and includes the above-mentioned high tensile elastic modulus reinforcing fiber. Most suitable as a reinforcing fiber for layers. However, it may be a layer containing two or more kinds of reinforcing fibers, for example, carbon fibers and glass fibers.

As the reinforcing fiber used for the central layer 3, for example, glass fiber can be used. However, this layer may also be a layer containing two or more kinds of reinforcing fibers, for example, glass fibers and carbon fibers. Each of the layers composed of such fiber bundles of reinforcing fibers is formed by compounding with a resin.

Thus, the FRP grating 1 according to the present invention
Has a high tensile elastic modulus reinforcing fiber in the outer layer (the outermost layer in the present embodiment) and a low tensile elastic modulus reinforcing fiber in the inner layer (center layer), so that deterioration of the member due to long-term use or excessive load First, delamination is caused by the shear stress generated at the interface between the outer layer and the inner layer before a large breakage due to fiber breakage occurs when the fiber is broken. When the load is further increased and the fiber is broken, a large breakage occurs.

The above-mentioned delamination is not a fracture mode as when the fiber breaks, but is a mode in which the rigidity of the member is simply lowered and the damage can be detected, but it is brittle and does not cause fatal damage. Therefore, this delamination is optimal as a danger prediction mode.

The stress that causes delamination depends on the tensile elastic modulus of the reinforcing fibers in the two types of reinforcing fiber layers and the distance from the bending center axis of the FRP member.

For example, when the thickness of the layer having the high tensile modulus reinforcing fiber exceeds 1/3 of the total thickness, the FR after peeling is increased.
The bending strength of the P member is about half of the initial strength, which is too low as the residual strength of the member after peeling. Also, 1
If it is less than / 5 (20%), the shear stress generated between the layers having two kinds of reinforcing fibers having different tensile elastic moduli is small, and there is a high possibility that the fiber breaks suddenly in the breakage, which may lead to failure prediction. May lose effect. Therefore, the thickness of the outermost layer preferably occupies at least 1/5 (20%) of the total thickness, and more preferably 1/5 to 1/3.

Further, the greater the difference between the tensile elastic moduli of the two types of reinforcing fibers, the greater the interlaminar shear stress when a load is applied, but if the difference is too large, peeling will occur at a low load. Since it will not be established as a grid member,
It is desirable that the high tensile elastic modulus reinforcing fiber has a tensile elastic modulus of 3 times or more, more preferably 3 to 7 times that of the low tensile elastic modulus reinforcing fiber.

Further, since the FRP lattice according to the present invention uses fibers having a higher tensile elastic modulus than the inner layer for the outer layer, the FRP lattice has high rigidity and the width of each lattice bar can be made small, thereby increasing the aperture ratio. 10 to 20 compared to conventional GFRP products
% Can be increased. As a result, an FRP grating having an aperture ratio of 65 to 95% can be easily constructed.

Further, as a result of the large aperture ratio, a small amount of material is used and the total volume is small. Furthermore, when the reinforcing fiber bundle contains carbon fibers, the specific gravity of the carbon fibers may be smaller than the specific gravity of the glass fibers, so that the weight of the entire member can be significantly reduced.

Thermosetting resins such as epoxy resin, vinyl ester resin, unsaturated polyester resin and phenol resin are mainly used as the resin to be used. Among them, the vinyl ester resin is excellent in chemical resistance and weather resistance. Therefore, it is preferable.

The matrix resin is not limited to the thermosetting resin, but may be nylon resin, ABS resin,
It may be a thermoplastic resin such as a polypropylene resin,
Further, a mixture of a thermosetting resin and a thermoplastic resin may be used.

Such a resin may be impregnated into a fiber bundle in advance, and may be shaped by shaping the bundle, or a preform that has been dry-molded may be impregnated with the resin later. . Further, it is also possible to perform defoaming in the vacuum chamber in order to eliminate voids after the fiber and the resin are combined. That is, the resin is cured and solidified under reduced pressure.

The FRP grating manufactured as described above can have excellent mechanical properties while being lightweight.
That is, the weight is not more 15 kg / m ² or less, and, and FRP grating bending stiffness of at least ^{0.7 × 10 6 kgf · mm 2} , the weight is at 15 kg / m ² or less, and flexural strength of at least F which is 40 kgf / mm ²
An RP grating can be realized.

FIG. 3 shows an FRP grating 1 according to another embodiment.
0 is shown. In the present embodiment, the pitch between the intersections of the grid bars arranged in two directions so as to intersect each other has a different vertical and horizontal pitch. Although not shown, the pitch between the intersections may be constant, or may be a type that changes midway.

In addition, the FRP grating 1 shown in FIGS.
In No. 10, the reinforcing fibers were arranged in layers in two directions and formed into a structure having a lattice bar extending in a direction substantially orthogonal to each other, but a structure having reinforcing fibers and a lattice bar extending in three or more directions, for example, obliquely. May be Furthermore, FIG.
Although the FRP having a three-layer structure is shown in FIG. 1, another cross-sectional layer structure can be used. For example, the inner layer may have a two-layer structure containing low tensile elastic modulus reinforcing fibers, and both outermost layers may be arranged with layers containing high tensile elastic modulus reinforcing fibers. In addition, a thin layer such as a GFRP layer can be provided on the surface for the purpose of imparting electrolytic corrosion resistance or for the purpose of protecting the outermost high tensile modulus fiber layer.

Further, the frame for forming the eyes of the lattice, that is, the cross-sectional shape of the lattice bar is not limited to the inverted trapezoidal shape shown in FIG. 2, but may be a trapezoid, a rectangle, an ellipse, a polygon,
An arbitrary shape such as a trapezoidal shape is possible, and the cross section is not limited to a simple shape but a complicated special shape.

Furthermore, in the embodiment shown in FIG. 2, the reinforcing fibers 2a and 2b containing the high tensile elastic modulus reinforcing fibers are arranged in both outermost layers, but the present invention is not limited to this embodiment. For example, as shown in FIG. 4 (A), with respect to the central layer 20, reinforcing fibers 21 a, 2 containing high tensile elastic modulus reinforcing fibers on both outsides thereof.
1b is placed on the outside of the layer 1b and another layer 22a, 22b
May be arranged.

Further, as shown in (B), as compared with the embodiment shown in FIG. 2, reinforcing fibers 24 containing high tensile elastic modulus reinforcing fibers are arranged only as one outermost layer, and the rest are all other reinforcing fibers. The configuration may be set to 23. Similarly, as shown in (C), as compared to the embodiment shown in (A), reinforcing fibers 26 containing high tensile elastic modulus reinforcing fibers are arranged only as one outer layer, and reinforcing fibers 25, 27 are provided on both sides thereof. May be arranged.

Further, as shown in (D), as compared with the embodiment shown in FIG. 2, the reinforcing fiber 2c containing the high tensile elastic modulus reinforcing fiber is also arranged in the center, and the other reinforcing fibers 3a and 3b are provided on both sides thereof.
May be arranged, and the reinforcing fibers 2a and 2b may be arranged in the outermost layer.

That is, in the FRP lattice according to the present invention, at least one outer layer may be formed by using reinforcing fibers including high tensile elastic modulus reinforcing fibers.

Furthermore, as shown in (E), a structure having a step in the cross section of the lattice may be adopted. In the illustrated example, FIG.
As compared with the embodiment shown in FIG. 7, the reinforcing fiber 28 portion including the high tensile elastic modulus reinforcing fiber is enlarged, and the step portion 29 is formed between the reinforcing fiber 28 and the central layer 3.

The FRP grating as described above has at least 2
It is formed using a mold having a grid forming groove extending in the direction. For example, the FRP grating 1 shown in FIGS.
A molding die for molding is as shown in FIG. The molding die 30 is formed with molding grooves 31 extending in two directions (in this embodiment, two directions orthogonal to each other).
The cross section of each forming groove 31 is formed in a shape corresponding to the inverted trapezoidal shape shown in FIG.

In such a molding die 30, for example, as shown in FIG.
The reinforcing fibers 2b, 3 and 2a as shown in FIG. 3 are sequentially arranged in layers and resin is injected to mold the FRP lattice.
The reinforcing fibers 2a and 2b include high tensile elastic modulus reinforcing fibers, and the reinforcing fibers 2a and 2b are arranged in the outer layer. If molding is performed under reduced pressure, degassing can be performed efficiently, and a voidless FRP lattice can be obtained.

As the molding die, a die as shown in FIG. 6 can be used. In the forming die 40 shown in FIG. 6, the groove 4 extending in the thickness direction of the forming die 40 is formed on the side wall 41a of the forming groove 41, that is, on the side wall 41a of the die forming the grid pattern.
2 is engraved. The groove 42 may be provided on all side walls, or may be provided only on some side walls. Although the groove 42 is formed as a V groove in the present embodiment, the cross-sectional shape of the groove 42 can be any shape such as a U shape, an arc shape, a square shape, or a trapezoidal shape.

When the groove 42 extending in the thickness direction of the molding die 40 is provided on the side wall 41a in this manner, when the resin is injected into the molding die 40 in which the reinforcing fiber bundle in the dry state is laminated in the molding groove 41. Since the resin immediately reaches the bottom surface 41b of the molding groove 41 or near the bottom surface through the groove 42,
The impregnation of the resin into the reinforcing fiber becomes faster. Further, air remaining in the reinforcing fibers even after the resin impregnation becomes easy to escape through the grooves 42, and voids in the FRP lattice can be reduced.

Furthermore, if the molding die 40 after resin injection is placed in a vacuum chamber or the like and molding is carried out under reduced pressure, a more voidless FRP lattice can be obtained.

Groove 4 of the mold for manufacturing such FRP lattice
2 is preferably provided in a direction substantially perpendicular to the molding groove bottom surface 41b as shown in FIG. 6 in view of ease of resin entry and air escape, but even if provided obliquely. I do not care. The groove 42 may have any size, but it is preferable that the width is 10 mm or less and the depth is 5 mm or less. If the width exceeds 10 mm, the laminated reinforcing fibers may bend along the grooves 42 and block the grooves 42, so that the above-mentioned effects cannot be sufficiently obtained. When the depth of the groove 42 exceeds 5 mm, the groove 4
2, the weight of the cured resin increases, and there is a possibility that a sufficient lightening effect as the FRP lattice cannot be obtained.

The groove 42 is the side wall 41a of the molding groove 41.
Although it is preferable to penetrate from the bottom surface 41b to the top surface of the above, it may be cut off in the middle if the above-mentioned effect is obtained. Further, the number of the grooves 42 may be one or more on the side wall of the forming groove of each lattice portion, but the effect is greater if the number of the grooves 42 is one or more on the side wall of the forming groove on each side of each lattice.
However, at this time, if five or more grooves 42 are provided on the side walls of the molding grooves on each side of each lattice, it is necessary to pay attention because the resin that has entered the grooves and hardened may not be able to obtain the lightening effect. It is.

An FRP lattice molded by using the molding die 40 as described above is, for example, as shown in FIG. FRP
Protrusions 51 extending in the thickness direction of the lattice are formed on the side surfaces of each lattice portion of the lattice 50, corresponding to the grooves 42 shown in FIG. The size, length, and cross-sectional shape of the ridge 51 correspond to those of the groove 42 described above. The FRP grating 50 as described above is lightweight, has high rigidity, and has high strength characteristics.
It will be a high quality of the dress.

[0055]

Embodiments of the present invention will be described below. Example 1 Forming grooves are arranged in a grid, and the dimensions are 1
007mm, thickness 50mm, pitch between lattices 40m
The reinforcing fibers (A) of the carbon fibers and the reinforcing fibers (B) of the glass fibers, which had been aligned, were laminated in a two-direction A / B / A laminated structure to a predetermined thickness on a molding die of m. Then, resin was injected into the laminated fibers, impregnated and cured. After curing, the molded product was taken out, surface-processed to a thickness of 40 mm, and further cut out to a length of 1,007 mm × width of 407 mm. The lattice section is shown in FIG. The dimensions of the horizontal cross section of the frame forming the grid pattern were an upper surface width of 4.5 mm, a lower surface width of 2.5 mm, and a thickness of 40 mm. This molded product was simply supported at both ends (span interval 600 mm) and subjected to a bending test under a central concentrated load.

The results are shown in Table 1. Both the strength per unit weight and the rigidity of the molded product were significantly superior to those of the conventional GFRP lattice. Further, the destruction mode was also high in safety because the interlayer destruction preceded.

[0057]

[Table 1]

[0058]

As described above, the FRP lattice of the present invention is lightweight and has excellent mechanical properties such as bending rigidity and bending strength. Further, according to the FRP lattice of the present invention, since the outer layer has the layer containing the high tensile elastic modulus reinforcing fiber, the tensile elasticity can be improved when the material deteriorates under long-term use or when an excessive load is applied. 2 with different rates
It becomes possible to predict before a large breakage occurs due to the breakage of the fibers when peeling occurs between the layers of the reinforcing fibers of the seed, and a member excellent in safety can be realized.

Further, since the reinforcing fiber having a high tensile elastic modulus is used for the outer layer, the member rigidity is increased and the width of the lattice bar can be reduced, so that the aperture ratio can be increased, the drainage property, the see-through property and the ventilation property. And the like, and the performance as an FRP grating is improved.

Further, since the amount of materials used is reduced, it is possible to greatly reduce the weight. Further, the material cost is reduced due to the reduction of the used material, and at the same time, the working time is reduced, so that the cost can be reduced as compared with the conventional product.

Further, if the outer layer, particularly the outermost layer, is a layer having carbon fibers, the chemical resistance and water resistance can be further improved.

Further, by using the molding die according to the present invention, which has grooves extending in the thickness direction of the molding die on the side wall of the die for forming the grid pattern, the reinforcing fiber can be laminated in the molding die in a dry state. The production efficiency is good, and the FRP lattice of any size can be easily manufactured. Furthermore, since it can be made into a void dress, it is possible to manufacture an FRP grating having higher strength and rigidity.

[Brief description of drawings]

FIG. 1 is a partial perspective view of an FRP grating according to one embodiment of the present invention.

FIG. 2 is an enlarged partial cross-sectional view of the FRP grating of FIG.

FIG. 3 is a partial perspective view of an FRP grating according to another embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of yet another embodiment of the FRP grating according to the present invention.

FIG. 5 is a partial perspective view of the molding die for manufacturing the FRP lattice shown in FIGS. 1 and 2.

FIG. 6 is a partial perspective view of another mold for manufacturing an FRP lattice according to the present invention.

FIG. 7 is a partial perspective view of an FRP lattice molded using the molding die of FIG.

[Explanation of symbols]

1, 10, 50 FRP lattice 2a, 2b, 21a, 21b, 24, 26, 28 Outer layer containing high tensile modulus reinforcing fibers 3, 3a, 3b, 20, 23, 25 Central layer containing low tensile modulus reinforcing fibers (Inner layer) 22a, 22b, 27 Other outer layers 29 Steps 30, 40 Mold 31, 41 Molding groove 41a Side wall 41b Molding groove bottom 42 Groove 51 Projection

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location B29K 307: 04 309: 08 B29L 9:00 31:10 (72) Inventor Hiroshi Onishi Iyo-gun, Ehime Prefecture Matsumae-cho 1515 Tsutsui, Toray Co., Ltd., Ehime Plant (72) Inventor Nobuhiko Shimizu Matsumae, Iyo-gun, Ehime Prefecture Matsumae-cho, Toray Co., Ltd. 1515 Tsuji, Otsuji Toray Co., Ltd. Ehime factory

Claims (21)

[Claims] 1. A weight of 15 kg / m ² or less, and a bending rigidity of at least 0.7 × 10 ⁶ kgf · mm.
FRP grating characterized by being ² . 2. An FRP grating having a weight of 15 kg / m ² or less and a bending strength of at least 40 kgf / mm ² . 3. An FRP lattice in which reinforcing fibers are arranged in layers and are composited with a resin, wherein the reinforcing fibers include high tensile elastic modulus reinforcing fibers and low tensile elastic modulus reinforcing fibers, and at least an outer layer. Contains a high tensile elastic modulus reinforcing fiber. 4. The FRP grating according to claim 3, wherein the aperture ratio is in the range of 65 to 95%. 5. The FRP lattice according to claim 3, wherein the frame forming the eyes of the lattice has an inverted trapezoidal cross-sectional shape. 6. The FRP grating according to claim 3, wherein a step portion is provided in a cross section of a frame forming the eyes of the grating. 7. The FRP lattice according to claim 3, wherein a ridge extending in the thickness direction of the lattice is provided on a side surface of a frame forming the lattice eyes. 8. The FRP lattice according to claim 3, wherein the resin is a vinyl ester resin. 9. The FRP lattice according to claim 3, wherein the high tensile elastic modulus reinforcing fibers are carbon fibers and the low tensile elastic modulus reinforcing fibers are glass fibers. 10. The tensile modulus of the high tensile modulus reinforcing fiber is at least three times that of the low tensile modulus reinforcing fiber,
The FRP grating according to any one of claims 3 to 9. 11. The outer layer has a thickness of at least 2 of the total thickness.
The FRP grating according to any one of claims 3 to 10, which occupies 0%. 12. The weight is 15 kg / m ² or less, and the bending rigidity is at least 0.7 × 10 ⁶ kgf · mm.
The FR according to any one of claims 3 to 11, which is ^2.
P lattice. 13. The weight is 15 kg / m ² or less, and the bending strength is at least 40 kgf / mm ² .
The FRP grating according to any one of claims 3 to 12. 14. A civil engineering / construction member having the FRP lattice according to any one of claims 1 to 13. 15. A mold for an FRP lattice formed by arranging reinforcing fibers in layers and compounding with a resin, wherein a groove extending in the thickness direction of the mold is provided on the side wall of the mold forming the mesh of the lattice. A mold for an FRP lattice, which is characterized in that 16. Reinforcing fibers are arranged in layers in a mold,
When manufacturing a FRP lattice by injecting a resin, as the reinforcing fiber, a high tensile elastic modulus reinforcing fiber and a low tensile elastic modulus reinforcing fiber are used, and at least the high tensile elastic modulus reinforcing fiber is arranged in the outer layer. A method for manufacturing an FRP grating, which is characterized. 17. A method for producing an FRP lattice, comprising arranging reinforcing fibers in layers in the mold of claim 15 and injecting a resin to produce an FRP lattice. 18. The method for producing an FRP lattice according to claim 16, wherein the forming is performed under reduced pressure. 19. The method for producing an FRP lattice according to claim 16, wherein a vinyl ester resin is used as the resin. 20. The FRP lattice according to claim 17, wherein the high tensile elastic modulus reinforcing fiber and the low tensile elastic modulus reinforcing fiber are used, and the high tensile elastic modulus reinforcing fiber is arranged at least in the outer layer. Manufacturing method. 21. The method for producing an FRP lattice according to claim 16, wherein carbon fiber is used as the high tensile elastic modulus reinforcing fiber, and glass fiber is used as the low tensile elastic modulus reinforcing fiber.